Process for the production of succinylosuccinic diesters

ABSTRACT

A NOVEL PROCESS FOR THE PRODUCTION OF SUCCINYLOSUCCINIC ACID DIESTER IS DISCLOSED. THE PROCESS INCLUDES REACTING A Y-HALOACETOACETIC ESTER WITH A STRONG BASE. THE REACTION IS CONDUCTED IN THE PRESENCE OF AN AQUEOUS BUFFER SOLUTION OF AT LEAST ONE INORGANIC SALT AT A PH OF 8 TO 10. THE REACTION IS CONDUCTED AT A TEMPERATURE BETWEEN -10 AND 10*C., PREFERABLY BETWEEN -2* AND 0*C. THE SUCCINYLOSUCCINIC ACID DIESTER CAN BE ISOLATED BY ANY CONVEINT METHOD SUCH AS FILTERING OR CENTRIFUGING IT FROM THE REACTION SOLUTION.

United States Patent'iO 3,803,209 PROCESSFOR THE PRODUCTION OF V j SUCCINYLOSUCCINIC DIESTERS Erich Greth, Visp, Switzerland, assignor-to Lonza Ltd., Basel, Switzerland No Drawing. Filed July 13, 1972, Ser. No. 271,359 Claims priority, application Switzerland, Mar. 22, 1972, 4,237/72 Int-Cl. C07c 69/74 US. Cl. 260-468 K 16 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THIS INVENTION (1) Field of this invention This invention relates to a process for the production of'succinylosuccinicacid diester from 'y-haloacetoace'tic ester and a strong base in a water medium.

(2) Prior art Succinylosuccinic acid diester has been produced by reaction from 'y-chloroacetoacetic ester in water by reaction with sodium phenolate; in that case, a yield of only 58 percent was obtained (Bull. Soc. Chim. France 29, 192, pp. 402-6).

Succinylosuccinic acid diester has been produced from succinic aciddiethyl ester (as a starting material). In that casethe succinic acid diethyl ester was reacted with sodium ethyl-ate. The highest yield that was achieved by that process was around 80 percent (US. :Pat. No. 3,024,268). The main disadvantage of that process, how ever, is thattheisolation of the resultant succinylosuccinic acid diester is exceedingly cumbersome, diflicult and time -consuming. Furthermore, large quantities of solvent are needed in that process.

Succinylosuccinic esters have been prepared from ethyl succinate and Na using a double Claisen reaction. Whitmore, F. C., Organic Chemistry," 2nd ed. (1951), p. 381. vSuecinylosuccinic esters have been produced. by reacting. NaOC I-I and ethyl succinate. Whitmore, ibid, p. 708.

BROAD DESCRIPTION OF THIS INVENTION object of the invention is to produce succinylosuccinic acid .diester from 'y-haloacetoacetic ester in high yields using a simple process. a

The process of this invention involves the production ofsuccinylosuccinic acid diester. The process includes reacting a 4-halo-acetoacetic acid esters having the formula:-

by anyconvenient method such as filtering or centrifuging it from the reaction solution. The product has a white to DETAILED DESCRIPTION OF THIS INVENTION The pH of the reaction solution must be retained between 8 and 10, preferably between 9 and 10, and most preferably at 9.5.

The required pH range during the reaction or conversion is maintained by the use of an aqueous buffer solution, the buffer being comprised of at least one inorganic salt. Preferably the buffer is comprised of two inorganic salts or an inorganic salt and a strong inorganic base (e.g., NaOH)."The preferred buffer is a mixture of Na OO and NaHCO being preferably used at a ratio of 0.5 to 1.5 moles of Na OO When the buffer is a mixture of NaHCO and NaOH their ratio is preferably 1 mole of NaHCO to 0.2 to 0.8 mole NaOH. An example of another useful bufier is a mixture of Na2B4o and sodium hydroxide.

The reaction is conducted at a temperature between 10 and 10 0., preferably between 2 and 0 C.

The strong base should be a strong inorganic base. The strong base should have a dissociation constant (k), in aqueous solutions, of at least 1 l0- and preferably of at least 1x10 Examples of useful strong inorganic bases are: sodium hydroxide (most preferred); potassium hydroxide; barium hydroxide; and calcium hydroxide. Mixtures of strong bases can be used.

The'y-haloacetoacetic acid esters are usually prepared from an alcohol and -y-haloacetoacetic acid chloride. R in the ester formula can be any alkyl group containing one to ten carbon atoms and can be a straight chain or branch chain alkyl group. Examples of useful alkyl groups which R can be are: methyl, ethyl (preferred) n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, n-hexyl, n-heptyl, n-,octyl, n'-nonyl, n-decyl, neo-pentyl, 2,4-.dimethyl-3-pentyl', Z-heptyl, 3-heptyl, 2-methyl 2 heptyl, 3rnethyl-2-heptyl, 4-heptyl, 2,6-dimethyl, 4-heptyl, 4-ethyl-4-heptyl, 2-methyl-l-heptyl', 4-methyl 4-heptyl, 3-methyl-l-heptyl, 4-propyl-4-heptyl, 4-methyl-lheptyl, 2,2,3,3-tetramethyl butyl, 2,3-dimethyl pentyl, 2, 2,4-trimethyl pentyl, 2,4-dimethyl-3-ethyl-3-hexyl, 2- ethyl-hexyl, 2-butyl, t.-butyl, Z-methyl-l-butyl, 2-pentyl, 3-pentyl, 3-methyl'2-butyl, 2-methyl-2-butyl, Z-methyl-lpentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl,- 2-ethyl-lbutyl, t.-amyl, 2,3-dimethyl-l-butyl, 2-hexyl, 3-hexyl, 3- methyl-Z-pentyl, 2,2 -dimeth vl-3-but yl, 4-methyl-2-pentyl, 2,3-dimethyl-2-butyl, 2-methyl-3-pentyl, and 3-methyl-3- pentyl, and 2-methyl-2-pentyl. PreferablyR is an alkyl group having one to four carbon atoms.

As used herein X can be chlorine, bromine, iodine or fluoride, but chlorine is preferred. I [,Examples of useful 'y-haloacetoacetic acid esters are: "ychloroacetoacetic acid ethyl ester (preferred),. 'y-chloroacetoacetic acid methyl ester, 7-chloroacetoacetic 'acidn-propyl ester 'y-chloroac'etoaceti'c acid isopropyl ester, 'y-chloroacetoacetic acid n-butyl'ester, 'y-chloroacetoacetic acid isopentyl ester, y-ichloroacetoacetic acid n-hexylester,; w-chloroacetoacetic' acid n-decyl ester,

'7 'y-chloroacetoacetic acid 4-methyl-1-heptylester' -bromoacetoacetic acid. methyl ester 'y-bromoacetoacetic acid ethyl ester y-bromoacetoacetic acid n-propyl ester, :y-bro'moacetoacetic acid n-hexyl ester, 'y-fiuor'oaceto'acetic acid ethyl ester, and 'y-iodoacetoacetic acid ethyl ester.

R is defined above and can be different lower alkyl groups.

The succinylosuccinic acid diester can be isolated from the reaction solution by any conventional or convenient means such as filtering or centrifuging the reaction solution. The product is white to slightly yellowish in color and has a purity above 99 percent. I

The succinylosuccinic acid diester are used for the production of quinoacridone dyes and in the production of polymers.

In the following examples and throughout the rest of the application, all parts, ratios, and percentages are on a weight basis unless otherwise stated or obviously so to one ordinarily skilled in the art.

EXAMPLE 1 11.50 gm. of anhydrous sodium carbonate (0.108 mole) and 3.10 gm. of sodium bicarbonate (0.036 mole) were dissolved in water, the admixtures temperature was lowered to -1.5 C., and 11.88 gm. of 'y-chloroacetoacetic ethyl ester (0.072 mole) were added to theadmixture at 1.5 C. while stirring. After 24 hours,'the resultant precipitate was separated, by means of suction, at ---1.5' C. The removed precipitate was suspended in .150 ml. of water, was separated by means of suction, and

was then dried. 6.951 gm. of succinylosuccinic acid diethyl ester were obtained, which corresponds to ayield of..75.1 percent. The resultant ester had a purity of 99.8 percent and a melting point of 126.3 to 126.4 0.

EXAMPLE 2 Example 1 was repeated except that 11.738 gm. of 'y-chloroacetoacetic acid methyl ester was used in place of the 'y-chloroacetoacetic acid ethyl ester. 6.233 gm. of succinylosuccinic' acid dimethyl ester were obtained. The yield was 70.1 percent and the product had a melting point of 153.4 C. I

' EXAMPLE 3 YEXAMPLEA 15.20 gm. of sodium bicarbonate (0.18 mole) and 4.30 gm. of caustic soda solution (0.108 mole) were dissolved in 200 ml. of water. The solution temperature was reduced to -1.5 C. The reaction was conducted at 1.5

EXAMPLE Example 1 was repeated except that the reaction e58 conducted at 10 C.

EXAMPLE 7 Example 1 was repeated except thatan equal molar mix ture of 'y-chloroacetoacetic acid ethyl esters and 'y-chloroacetoacetic acid methyl ester was used in place of the 'ychloroacetoacetic acid ethyl ester.

EXAMPLE 8 Example 1 was repeated except that potassium hydroxide was used in place of the sodium hydroxide.

EXAMPLE 9 Example 1 was repeated except that barium hydroxid was used in place of the sodium hydroxide.

EXAMPLE 10 Example 1 was repeated except that 'y-chloroacetoacetic acid n-butyl ester was used in place of the 'y-chloroacetoacetic acid ethyl ester.

- EXAMPLE 11 Example 1 was repeated except that y-bromoacetoace-' tim acid ethyl ester was used in place of the 'y-chloroacetoacetic acid ethyl ester.

What is claimed is:

1. A process for the production of succinylosuccinic acid diester which comprises reacting a 'y-haloacetoacetic acid alkyl ester with a strong base, said reaction being conducted in an aqueous buffer solution of at least one inorganic salt at a pH of 8 to 10.

2. A process as described in claim 1 wherein said succinylosuccinic acid diester is recovered from said solution.

3. A process as described in claim 1 wherein said reaction was conducted at a pH of 9 to 10.

4. A process as described in claim 1 base is sodium hydroxide.

5. A process as described in claim 1 wherein said 7- haloacetoacetic acid ester is 'y-chloroacetoacetic acid ethyl wherein said strong ester.

C. while stirring after 11.712 gm. of 'y-chloroacetoacetic acid ethyl ester were added. After 24 hours, the precipitate was isolated by means of suction at -1.5.C. The product was suspended in 150 ml. ofwater, water isolated by means of suction and then dried. 6,746 gm. of

succinylosuccinic acid diethyl ester were obtained in a yield of 74.0 percent.

EXAMPLES Example 1 was repeated except that the reaction was'con- 6. A process asdescribed in claim 1 wherein said haloacetoacetic acid ester is 'y-chloroacetoaceti'c acid meth yl ester.

7. A process as described in claim 1 wherein said '7: haloacetoacetic acid ester is 'y-chloroacetoac'etic acid iso propyl ester. 8. A process as described in claim 1 wherein the alltyl' group in said q -haloacetoacetic acid ester has from one to four carbon atoms.

'9. A process as described in claim 1 wherein said aque-' ous buffer solution contains Na CO and NaHCO as the buffering components, said Na CO and NaHCO as the buffering components, said Na CO and NaHCO being present in a ratio of 0.5 to 1.5 moles of Na CO to 1.5 to 0.5 moles of NaHCO 10. A process as described in claim 9 wherein said reac tion is conducted at a temperature between --10 and 10 C.

' 11. A process as described in claim'l wherein said aqueous butter solution contains NaHCO and NaOH, said NaHCO and NaOH being present in a ratio of 1 mole of NaHCO to 0.2 to 0.8 moles of NaOH.

12. A process as described in claim 11 wherein said reaction is conducted at a temperature between -10 and a v 13. A process as described in claim 1 wherein said aqueous butter solution contains borax and NaOH, said borax and NaOH being present in a ratio of 1 mole'of borax to 0.08 to 1.5 moles of NaOH. j 14. A process as described in claim 13 wherein 'reac 5 tion is conducted at a temperature between 10 and v I. 6:

6 15. A process as described in claim 1 wherein said 7- References Cited haloacetoacetic acid ester has the formula: Hedelius, J" PhySik. Chem. 96 343 66 0 0 (1920). XCHQ-( E-OHr-( iOR 16iliouse, H. D. Modern Synthetic Reactions (1965) 163- wherein X is a halogen atom and R is an alkyl group containing one to ten carbon atoms.

16. A process as described in claim 15 wherein said re- LORRAINE WPINBERGER Primary Exammer action is conducted at a temperature between -10 and P. L. KIL'LOS, Assistant mi r 10 C. 

